How does the physical description of Huck's father in Chapter Five also serve to describe his character?

Huck describes Pap as a filthy, poor man who used to scare him a great deal. Now, however, Huck is no longer scared of Pap, and instead notes how old his father has grown.

Huck describes Pap as a filthy, poor man who used to scare him a great deal. Now, however, Huck is no longer scared of Pap, and instead notes how old his father has grown.